As a result of various health concerns and regulatory efforts there is a significant increase in the use of zero trans fats. This has resulted in significant cleaning problems for the food industry. For example, food processing equipment and/or environmental surfaces become contaminated with polymerized zero trans fat soils, which are very difficult to clean. Zero trans fats are less stable and more prone to degradation and polymerization than trans fats or saturated fats. Zero trans fats can be left on ambient or cold surfaces for an extended period of time and polymerize on these surfaces creating a difficult to clean soil. The longer a zero trans fat soil is left to polymerize on a surface, the more difficult it becomes to remove the soil from that surface. Mists of zero trans fats emanating from a hot zero trans fat source can also collect onto various surfaces and polymerize over time on these surfaces. The surfaces collecting these mists can be at cold, hot or ambient temperatures and create difficult to clean soils on all of these surfaces. Zero trans fats can be burnt onto cooking surfaces and then polymerize over time at an increased rate compared to a surface at a lower temperature and create soils that are more difficult to remove than similarly produced trans fat or saturated fat based soils. In addition, other food materials such as proteins, carbohydrates and other fats can be mixed in with the zero trans fats which, as they polymerize can also create complicated, harder to remove soils and residues than if the soils did not contain polymerized zero trans fat soils.
Those employing frying and baking operations are particularly affected by polymerized fat soils, because they use zero trans fats in high volumes. Also, these operations commonly route zero trans fats through tanks, lines, pumps and other processing equipment, which must be periodically cleaned but can in some operations go a significant amount of time between cleanings as required by the specific production process. In addition, other equipment, especially high, out of place piping, duct work (external as well as internal), roofs and ceilings, heating, cooling and air conditioning surfaces (HVAC), product freezers and coolers and many other surfaces in food manufacturing sites, can sometimes be left for days, weeks or months without thorough cleaning, collecting zero trans fat contamination and forming extremely hard to remove, polymerized zero trans fat soils. These soils can be so difficult to remove that in some cases, it would be less expensive to replace equipment than to pay for the intensive labor required to clean the surfaces properly. In order to permit food production operations to continue without major changes to equipment and food processing facility designs, a new method of cleaning is needed to permit extended food production time and to retain a safe, clean food processing environment.
Traditionally, highly alkaline and corrosive cleaning compositions are required to effectively remove zero trans fat soils. Commercially-available degreaser products rely upon the cleaning power of caustic or sodium hydroxide (see e.g. Easy Off™, Greasestrip Plus™) to go after polymerized grease soils. Often the pH of these cleaners is at least 12-13 or greater. In addition, the alkalinity of these cleaners is attributed to an alkali or alkaline earth metal hydroxide, for example, sodium hydroxide (NaOH) or caustic. Further description of exemplary high alkalinity products is provided in U.S. Patent Publication No. 2010/0317559, incorporated herein by reference in its entirety. Such products often contain 4-8% sodium hydroxide.
Many consumers do not wish to transport and/or handle highly alkaline and corrosive compositions as this presents a variety of safety concerns and hazards. This is a result of various requirements for personnel to use personal protective equipment (PPE) to reduce employee exposure to the hazardous or corrosive materials. PPE may include, for example, goggles, eye wash stations, masks and other protective equipment. Therefore, it would be desirable to provide a non-corrosive, lower pH cleaning composition that can disrupt the structure of polymerized zero trans fat soils to adequately remove this type of soil and thereby clean surfaces without requiring personnel to use PPE.
There are alternatives to using highly alkaline caustic degreaser products, including products containing monoethanolamine. However, these compositions are often limited as a result of regulations related to the VOC of the compositions. For example, certain products require less than 4% monoethanolamine (or total VOC, defined by having a vapor pressure less than 0.1 mm Hg at 20° C.) under state regulation and still require PPE as a result of the relatively high alkalinity. Additional alternatives include non-corrosive products using weaker alkalinity (pH around 11-12) cleaning agents which require more mechanical force to remove soils. For example, the cleaning products may include sodium carbonate or other non-hydroxide sources of alkalinity. Therefore, it would also be desirable according to the invention to provide cleaning compositions and methods to remove polymerized zero trans fat soils without requiring additional mechanical force.
The various degreaser compositions are also formulated as ready to use (RTU) compositions. Therefore, it is desirable to obtain a concentrated formulation according to the embodiments of the invention.
Accordingly, it is an objective of the claimed invention to develop a non-corrosive degreaser concentrate which produces a use solution with a pH below about 11.5.
A further object of the invention is to develop a non-corrosive degreaser concentrate providing equal cleaning efficacy as some alkali metal hydroxide (i.e. caustic) formulations, wherein the compositions of the present invention comprise less than 1% sodium hydroxide, preferably excluding sodium hydroxide.
A further object of the invention is methods of cleaning using a non-corrosive degreasing concentrate that does not require use of PPE.